约束网络法在RC有源滤波器中的应用

介绍一种新的约束网络分析法来分析含有运算放大器的网络，并以ＲＣ有源滤波电路为例，进行了较细致的研究。认为用约束网络法较为简洁，方便，且具有普遍性。     

RC有源滤波器的计算机仿真设计

<正> 集中参数RC有源滤波器的传统人工设计方法在设计时颇费工夫,由于情况的复杂性,往往所得的滤波器的元件数目并不是最节省的,其特性也并不是最理想的。本文所述的设计方法,是直接从工程上预给的特性要求出发,由计算机按一定的步骤自动地准确地给出,能满足工程要求的集中参数RC有源滤波器的特性及元件的数值。由于可进行计算机的频率扫描仿真,根据仿真描绘出来的频率响应曲线,可随时对不满意的参数进行修改,屏幕立即显示出新的频率响应曲线,不断地重复该过程直到满意时为止。这样,设计的结果非常直观,得出的滤波器的元件数目最少、特性最理想,而所费的工夫却很少。该方法是在假设滤波器中的元器件为理想的情况下(即假设电阻R为纯电阻、电容C为纯电容、运算放大器为理想的放大器)进行设计的,因此在实际工作频率太高时,设计误差可能过大。如果选择的运算放大器其最高工作频率远远大于实际工作频率,则在设计工作频率为1MHz以下的滤波器时,一般情况下其工作误差均能够满足实际工程的需要。     

用有源RC滤波器实现网络综合的方法

在模拟滤波器的设计中,综合转移函数的方法总的来说分为两类,即用无源网络综合和用有源网络综合实现.目前常用的是用有源RC网络综合实现滤波器,实现有源RC滤波器的基本方法有直接法和级联法.文中介绍了级联法实现有源RC滤波器的典型过程,用此方法列举了一个高通滤波器的实现,并得到了正确的仿真图.     

RC—Nullor网络的一种拓扑分析方法及不定导纳矩阵的形成

本文提出了一种ＲＣ－ｎｕｌｌｏｒ网络拓扑分析的简便方法，并着重研究这种方法中不定导纳矩阵的直接形成。     

一种有源RC复数滤波器的设计方法

提出了一种采用有源RC滤波器实现复数滤波器时可快速确定无源器件参数值的设计方法.设计了一款中心频率为2MHz,带宽为2.4MHz的有源RC复数滤波器,并对自动频率调谐系统进行了分析.     

RC－Nullor网络的一种拓扑分析方法及不定导纳矩阵的形成

本文提出了一种ＲＣ－ｎｕｌｌｏｒ网络拓朴分析的简便方法，并着重研究这种方法中不定导纳矩阵的直接形成．     

单片有源RC滤波器UAF42及其应用

UAF42是高集成度的有源RC滤波器，本文介绍了UAF42的功能和特点，并给出了应用实例。     

A multi-standard active-RC filter with accurate tuning system

of calibration consumes 2 mA. The circuit has been fabricated in a 0.35μm 47 GHz SiGe BiCMOS technology; the receiver and transmitter filter occupy 0.21 mm2 and 0.11 mm2 (calibration circuit excluded), respectively.     

一种带有精确调谐系统的多标准有源RC滤波器

本文介绍了一种低功耗、高线性度、多标准有源RC滤波器,此滤波器带有设计巧妙而精确的调谐系统。该滤波器使用在IEEE 802.11a/b/g (9.5MHz) 和 DVB-H (3MHz, 4MHz)系统中。滤波器使用数字控制多晶硅电阻阵列和锁相环技术的调谐系统,它提供了4%以内的调谐精度。为了节约功耗和减小数字信号的干扰,它在调谐之后可以自动关闭。滤波器带外3阶交调量26dBm。群延时差值为50ns。接收和发送滤波器分别消耗3.4mA和2.3mA, 电源电压为2.85V,调谐系统消耗2mA。此电路采用0.35微米、47GHz锗硅BiCMOS工艺。接收滤波器和发送滤波器的面积（除去校正系统）为0.21-mm2和0.11-mm2。     

Micropower active-RC channel filter for a zero-IF Bluetooth receiver

A fourth-order low-pass channel filter for a zero-IF Bluetooth receiver is presented. It employs two cascaded multiple feedback biquads and active resistors made by quasi-floating gate MOS transistors in triode region for highly linear continuous tuning. Power consumption is strongly reduced using a gain-enhanced class-AB single-stage opamp together with a filter topology that only requires a single opamp for each biquad. The filter has been fabricated in a 0.18 μm CMOS technology and consumes 290 μW from a 1.2 V supply.     

A modified canonic active-RC bandpass filter with reduced sensitivity to amplifier gain-bandwidth product

A new configuration for activating a passive-RC bandpass building block to realize an inverting selective bandpass filter is described. The proposed network has the advantages of being canonic, is always stable, and has reduced sensitivity to the amplifier gain-bandwidth product.     

The derivation of switched-capacitor filters from active-RC prototypes

A general procedure is given for the design of an active switched-capacitor filter from an actlve-RC model. The process is based on trapezoidal integration. The resulting sampled-data circuit response is related to that of the model through the bilinear z-transformation.     

A design philosophy for microelectronic active-RC filters

A design philosophy for microelectronically realizable active-RC filters is presented and illustrated by means of microelectronic filter examples in the frequency range from approximately 75 Hz to about 110 kHz. The design is by simulation of low-sensitivity resistively terminated inductor-capacitor filters (LCR filters). Based on an analysis of the effect of nonideal components in the active-RC filters, functional adjustment methods are developed which lead in practice to near-ideal nominal response characteristics, in many cases better than those of practical LCR filters. By matching the design process to a carefully chosen well-established manufacturing technology, the cost of the microelectronic active-RC filters is attractively low. Many of these filters in microelectronic form are in production in the U.K.     

A new active-RC circuit realization of floating inductance

A new circuit which uses a single second generation current conveyor (CCII) [1], a single capacitor, and only two resistors and which simulates a lossy frequency-independent floating inductance without requiring any equality constraint is presented.     

网络分析仪在滤波器测试中的应用

为解决某型非标准阻抗滤波器由于测试系统老化带来的测试问题,利用网络分析仪实现了滤波器的测试.介绍了旧测试系统与网络分析仪的测试原理和它们之间的区别,阐述了网络分析仪Agilent E5071C替代频率特性测试仪BT-3、信号源XFC-6、超高频毫伏表QF2270、频率计8000C四台仪表测试滤波器的实现方法.实验证明,用网络分析仪测试数值一致性好、操作简单、精度高、减少了工作量、提高了生产效率.